It has been a practice in my place, that the first delivery of a woman should be in his parents' home to which I have no objection as it is not way contrary to Islam to my knowledge. They usually send the wife to her mother's house after 7 months. Before she is sent they do a kind of ceremony called Satwasa, which I feel is a practice of Hindus.
I appreciate if you through light on it based on Qur'an and Hadeeth. As I want to avoid this practice, as it concerns me right now.

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

There is nothing in the Sharee’ah that stipulates that the first delivery of the woman should be in her mother's house. Nonetheless, such an act is not against the Sharee’ah if the husband accepts it; it also might be appropriate as the woman in such circumstances is worried and may prefer to be near her mother.

As for the habit of getting together in the manner you described, if it is linked in anyway to Hinduism, then it is forbidden, because anyone who imitates a people is one of them.

The mentioned custom causes many difficulties to the woman's family, especially poor families. We mention some bad consequences of this custom.

1. Making a custom something which is not compulsory in Islam is prohibited in the Sharee’ah.

2. This custom may cause wasting money in unnecessary things, and such is forbidden in the Sharee’ah.

3. In many cases where the family of a given woman does not practice this custom, it is accused of stinginess and shame is brought to such a family. Moreover, the husband and his family hurt the woman mentally and sometimes physically too.

Doing so is from the pre-Islamic practices and has no place in Islam and distracts from its good teachings.

4. Many scholars believe that the origin of this custom is from Hinduism; if so, practicing it means imitating non-Muslims.
Finally, from the above details, it could be considered forbidden or at least disliked.

Remember that getting together for meals should be within the limits of the Sharee’ah. There should not be any mixing between men and women who are marriageable, on such occasions.

Allah knows best.